From the Richmond Daily Whig, 4/8/1863

A Prisoner Killed. - Two prisoners confined in Castle Thunder
attempted to escape on Saturday night, and by working a hole through a
partition, succeeded in getting upon the front balcony of the establishment. One
of them, seeing the guard on the watch, returned into the prison. The other was
proceeding to enlarge his area of freedom, when the guard fired, and shot him
through the head, killing him almost instantly. The prisoner was called Charles
Carroll, alias John Byass. - He was confined in the Castle for deserting from
the 54th Virginia regiment, where he had been accepted as a substitute.